Related Experiment Video
Updated: May 12, 2026
Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle
Published on: February 1, 2017
Early kinetics of innate and adaptive immune responses during hepatitis B virus infection
P Fisicaro1, C Valdatta, C Boni
1Laboratory of Viral Immunopathology, Unit of Infectious Diseases and Hepatology, Azienda Ospedaliero-Universitaria di Parma, Via Gramsci, 14, 43100 Parma, Italy.
Background And Aims:
Innate immunity appears to be silent in acutely hepatitis B virus (HBV)-infected chimpanzees, as shown by microarray analysis of intrahepatic gene expression. Whether this observation also applies to HBV pathogenesis in man remains undefined. The aim of this study was thus to characterise natural killer (NK) and CD56(+) natural T (NT) cell responses early after human HBV infection and their relationship to the induction of adaptive immunity.
Methods:
Two HBV-seronegative blood donors who became hepatitis B surface antigen (HBsAg) and HBV DNA positive but had persistently normal alanine aminotransferase (ALT) were followed from a very early stage of HBV infection. The phenotype (CD69 and NKG2D) and function (cytotoxicity and interferon gamma (IFN gamma) production) of NK and NT cells were analysed. CD4- and CD8-mediated responses were studied in parallel with overlapping peptides covering the entire HBV sequence by ex vivo intracellular cytokine staining (ICS) for IFN gamma, interleukin 2 (IL2), IL4 and IL10, and by ex vivo Elispot for IFN gamma. Healthy subjects, and patients with chronic and acute HBV infection were studied for comparison.
Results:
An early induction of both innate and adaptive responses was observed. NK and NT cells showed faster kinetics than HBV-specific T cells with an earlier peak of activity, while CD4(+) and CD8(+) cell responses were mounted with a similar profile, with higher frequencies of IFN gamma-producing CD8(+) cells at the peak of the response.
Conclusions:
The innate immune system is able to sense HBV infection, as shown by the early development of NK and NT cell responses, which probably contribute to contain the HBV infection and to allow timely induction of adaptive responses.
More Related Videos
10:37Analysis of HBV-Specific CD4 T-cell Responses and Identification of HLA-DR-Restricted CD4 T-Cell Epitopes Based on a Peptide Matrix
Published on: October 20, 2021
11:34A Competent Hepatocyte Model Examining Hepatitis B Virus Entry through Sodium Taurocholate Cotransporting Polypeptide as a Therapeutic Target
Published on: May 10, 2022
Related Concept Videos
01:24B Cell Activation and Differentiation
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
01:22Development of Immunocompetence
The initial cells that migrate from the fetal thymus settle within the skin and epithelial tissues lining the mouth, digestive tract, and in females, the uterus and vagina. These cells, including skin-based dendritic cells, serve as antigen-presenting cells, playing a key role in T cell activation.
Subsequent T...
01:29Immune Response Against Viral Pathogens
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
01:22Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test
01:25Hepatitis
01:28Viral Hepatitis I: Introduction